Field of the Disclosure
The teachings in accordance with the exemplary embodiments of this present disclosure generally relate to an automatic train operation system in railway vehicles configured to control a railway vehicle speed according to fault diagnosis of the propulsion system by diagnosing the fault of propulsion system that generates traction in automatically or unmannedly operated railway vehicles.
Discussion of the Related Art
This section provides background information related to the present disclosure which is not necessarily prior art. The railway vehicles may be interchangeably used by trains.
In general, railway vehicles under manual operation are run by traction when an engineer manipulates a controller in an operation room to input a propulsion notch and transmits an input of the propulsion notch to generate the traction, and the railway vehicles under automatic or unmanned operation are run by transmission of propulsion output by an engineer-replacing ATO (Automatic Train Operation) device to propulsion system of the railway vehicles according to a set speed profile.
If there is developed a fault in the propulsion system of a train to reduce the performance of the train, the drawback is that the train speed becomes slowed due to no generation of traction expected by the engineer or the ATO device from the propulsion output. Furthermore, a train cannot start when there is a failure in the propulsion system of the train. The propulsion system may include an encoder configured to generate an output from an engineer or ATO device in a PWM (Pulse Width Modulation) signal, a traction control unit configured to control a motor speed, and motor and interfaces installed on each driving unit.
In case of manual operation by an engineer, it may be possible to check abnormality of the propulsion system by grasping the traction expected by the engineer and actual movement of train, it is not easy to check the abnormality by train-mounted attendants or control center in case of automatic or unmanned operation by ATO device.
When performance deterioration is generated from the propulsion system, a train may run at a speed lower than an expected speed, whereby the train may arrive at a station at a delayed time due to failure to meet the set operation time, resulting in operation schedules all fouled up.
The prior art of Korean Laid-Open Patent No. 10-2009-0077587 discloses a motor fault diagnosis system in an electric train, where temperatures of inner coils, enclosures and air intakes of motors installed at each train are detected, and when there is a sudden change in temperatures, the sudden change in temperatures is determined as a fault, and temperature information of relevant motor at the changed point, running train speed, position information and master controller status are recorded, which are transmitted to the control center.
Furthermore, the Korean Laid-Open Patent No. 10-2009-0077587 also discloses that fault of a certain motor is remotely grasped when a relevant train is operated by a train operation manager to allow a fast maintenance and repair by accurately recognizing a fault generation time, a speed at the fault generation time and propulsion status at the time of generation of fault.
As discussed above, the prior art has proposed a method of diagnosing a motor fault in the propulsion system of electric train, where temperatures of inner coils, enclosures and air intakes of motors installed at each train are detected, and when there is a sudden change in temperatures, the sudden change in temperatures is determined as a fault.
However, in viewpoint of fault in the propulsion system or performance deterioration, the fault may be caused by various reasons including short-circuits between a propulsion notch output in the ATO device and a PWM generation device, abnormality at the PWM generation device, abnormality of interface between the PWM generation device and the propulsion system or abnormality at the motors.
Thus, the prior art suffers from disadvantages in that it is difficult to diagnose faults or performance deteriorations generated by other reasons when the fault is determined only by detecting an over-heat of a motor.